Why Thickness Changes the Cut Even When the Material Name Stays the Same
A thicker sheet gives the blade, beam, or jet more distance to wander, taper, or heat. Measure a coupon at this thickness before you reuse an old kerf.
Kerf
What the cutter removes, and how that slot is measured before it is trusted on a job.
What a Kerf Width Is Actually Measuring
Kerf width is the slot a saw, laser, plasma, or waterjet removes, not the finished part. Measure that slot on a test cut before the batch.
Cut a Test Coupon Before a Kerf Number Goes on a Batch
Measure a test coupon in the same material, thickness, and machine as the job before a kerf number is used on a batch.
How a saw, a laser, a plasma arc, and a waterjet open different slots in the same stock
A saw, laser, plasma arc, and waterjet each open a different slot. Remeasure the coupon when the process changes, even if the drawing does not.
How a kerf allowance changes the size you program
A kerf allowance moves the toolpath off the finished edge. Measure the slot on a coupon before you type an offset for the batch.